1. Field of the Invention
This invention relates generally to cooling transmission fluid, and, more particularly, to an automatic transmission oil pan having an oil-to-coolant heat exchanger.
2. Description of the Prior Art
Automatic transmission fluid (ATF) circulates continually through the transmission lubricating and cooling components that rotate at relatively high speed within a transmission case. The ATF, which is drawn by a pump from a transmission sump or oil pan located below, and secured to the transmission case, returns to the oil pan by gravity feed after circulating through the transmission. Its temperature increases in this flow path and must be lowered by passing through an oil cooler, which is usually located behind a radiator, in which heat from the engine coolant is transferred to an air stream flowing through the radiator. The system that supports this heat exchange consumes packaging space, is inefficient, costly, and cumbersome to assemble and service.
There is a need in the industry for a system and method for integrating an oil-to-coolant heat exchanger/cooler in a transmission oil pan. Heat transferred from the ATF to the coolant could be transported from the transmission to the radiator, where heat from the engine coolant is transferred to the airstream that flow through the radiator.